Known commercial power mowers are generally divided into three separate categories: self-propelled walk-behind mowers, ride-on mowers operated by a seated occupant, and stand-on mowers operated by a standing occupant.
For example, U.S. Pat. No. 4,920,733 discloses a typical walk-behind power mower. U.S. Pat. No. 5,865,020 discloses a typical ride-on mower where an operator sits on a seat during mower operation. U.S. Pat. Nos. 5,984,031, 5,964,082 and 5,507,138 disclose known stand-on mowers, each of these three patents hereby being incorporated herein by reference.
Deck lift systems for power mowers are also known in the art. For example, see the cutter deck lift system in U.S. Pat. No. 5,865,020, the disclosure of which is incorporated herein by reference. The mower or cutter deck is supported by a plurality of chains and a deck lift system enables the cutter deck to be raised and lowered in order to adjust the cutting height of the mower. Control arms (e.g., see reference numeral 40 in the ""020 patent) are utilized to control the lateral position or location of the cutter deck. Unfortunately, the control arms in the ""020 patent are rather long. Long control arms are needed in the ""020 system because the engine deck (upon which the engine is mounted behind the seat) does not move up/down along with the cutter deck during cutting height adjustment (i.e., the engine and engine deck remain fixed in place). Thus, the control arms are lengthy in order to reduce the amount of lateral movement of the cutter deck during raising/lowering operations in order to prevent large amounts of slack and/or tightness from building up in the pulley belt(s) which extend between the engine drive shaft and the blade pulleys mounted in top of the cutter deck. Unfortunately, long control arms means that the mower is more susceptible to damage caused by sideloads (e.g., when the side of the cutter deck is hit by something, or runs into an object such as a curb or tree).
Accordingly, it will be apparent to those skilled in the art that there exists a need in the art for a power mower deck lift system that can be designed so as to enable the efficient use of short control arms without overcomplicating the design of the mower. It is an object of this invention to fulfill this and other needs which will become apparent to the skilled artisan from reading the instant disclosure.
An object of this invention is to provide a deck lift system on a mower wherein control arms can be made short in length so as to make the mower more resistant to damage caused by sideload impact(s) on the cutter deck.
Another object of this invention is to provide a deck lift system on a mower wherein the cutter and engine deck assemblies (including the engine) are raised and lowered together as one unit when adjusting the blade cutting height of the mower.
Another object of this invention is to provide a power mower where the operator is capable of standing or sitting during different modes of mower operation.
Another object of this invention is to provide a mower where the battery(ies) can be located between feet of an operator in order to lower the overall center of gravity of the mower.
Another object of this invention is to provide a mower designed so that when going up a hill a mower operator can move from a sitting position to a standing position so that the overall center of gravity of the mower can be moved forward to minimize potential for tipping backward.
Another object of this invention is to provide a seat assembly which enables an operator to easily jump off of or abandon the machine.
Another object of this invention is to provide a seat on a mower, where the seat may be folded up into a storage or stowed position when the operator is standing on the mower or when there is a desire to transport or store the mower.
Another object of this invention is to provide a mower including a seat structure which is both comfortable and may be efficiently moved between deployed and non-deployed positions.
Another object of this invention is to provide a deck lift system which lifts an engine deck and a cutter deck together with one another, so that control arms utilized for positioning the deck can be designed to be shorter thereby enabling the deck assembly to be more resistant to negative impacts which may be caused by sideloads.
Yet another object of this invention is to satisfy or fulfill one or more of the above listedobjects.
Certain embodiments of this invention fulfill one or more of the above-listed needs and/or objects by providing a self-propelled power lawn mower comprising:
first and second rear drive wheels that are independently driveable so as to enable the mower to conduct approximate zero radius turns about a zero radius turning axis;
a foot platform for supporting at least one foot of an operator of the mower, said foot platform being located at an elevation less than an elevation of a top edge of at least one of said rear drive wheels;
a deck lift system for raising and lowering a cutter deck assembly, an engine deck, and an engine together as one unit in order to adjust a blade cutting height of the mower;
control arms pivotally attached to at least one of the cutter deck and engine deck in order to maintain lateral positioning of the cutter deck assembly and engine deck during the raising and lowering; and
wherein said control arms are short enough in length so that pivoting of the control arms an angle "PHgr" of fifteen (15) degrees either upward or downward during raising or lowering of the cutter deck assembly causes the cutter deck assembly to move a vertical distance xe2x80x9cdxe2x80x9d no more than about 2.5 inches.
Certain embodiments of this invention further fulfill one or more of the above-listed needs and/or objects by providing a self-propelled power lawn mower comprising:
at least one drive wheel;
a cutter deck assembly;
an engine;
a deck lift system for raising and lowering the cutter deck assembly and engine together in order to adjust a blade cutting height of the mower; and
pivoting control arms for helping maintain lateral positioning of the cutter deck assembly and engine during the raising and lowering.